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@Stewori Stewori released this 28 Oct 13:56
· 266 commits to master since this release

Release alpha 2 contains significant improvements over alpha 1. The main new feature is full
exception support. Exceptions filed in native code via Python C-API are translated to Jython
exceptions and can be accessed just like if they were generated by Python code. We added
a simple demo script JyNI-Demo/src/ to demonstrate this (did not want
to mess up with exception stuff).

Additionally, we support some new built-in types, compared to alpha 1. These are PySet,
PyFrozenSet, PyUnicode, PyClass, PyInstance, PyMethod and all built-in exception types.
Also the support of PyType was significantly improved.

One milestone in direction NumPy/SciPy is that JyNI is now able to use the original datetime
module. Jython features an own implementation of the datetime module, so this does not pay
off in new functionality right now. However, the original datetime module contains an own C-API
section that is not provided by Jython's version. Since NumPy uses this C-API, we will have to
use the original module. That JyNI alpha 2 is capable of using it, is demonstrated in

Another important improvement is that we finally managed to provide a makefile. Building JyNI is
much easier now. However, it is not as comfortable as an autotools-script - you may have to
adjust some variables in the makefile by hand, depending on your system. Mainly, you have to
specify, where Java and Jython can be found. Detailed instructions on building and using JyNI
are provided in the readme.

What still does not work is native garbage collection. We are going to address this in the next release. However, until garbage collection works, JyNI should not be used for much more than
demonstration purposes, since it would potentially leak a massive amount of memory if an extension crucially relies on garbage collection.

JyNI alpha 2 has been tested on

  • Linux Mint Debian edition (LMDE) (32 bit and 64 bit)
  • Linux Mint 13 (64 bit)
  • Ubuntu 13.10 (64 bit)

If you compiled it for another distribution, please consider to report your experience to If you are using a distribution not listed above, we would also appreciate
any feedback, whether you got the binaries working or what error you received if any.